Albert is right with the MIG. I have MIGed two broken exhaust manifolds that are still going strong (69 292 engine in 59 truck, and 47 cj2a) and I even redid the rear shock mounts on the rear axle of the 59 truck. 2 years, and a couple of 3000 lb loads ago. All still working good. Becuase of the localized heat of MIG its supposed to do well.
And as for the JB weld side, I even fixed an alternator mount on a phjord 302 in a MK VII. I didn't give it long, lasted the 5 years I had the car!
